Figure 3.

In vitro cellular uptake studies qualitatively by (A) fluorescence microscopy, and quantitatively by (B) flow cytometry in 4T1 cells. 4T1 cells were treated with C6-loaded nanoparticles 2 h before image. To further study the mechanism of cellular uptake, excess amount of HA or RGD was added and incubation for 30 min before uptake. ^∗∗P < 0.01 compared with C6@PVs micelle, ^##P < 0.01 compared with C6@PVHRs NP. Data were presented as mean ± SD (n = 3). (C) Confocal images of 4T1 cells treated with pDNA@PVHRs NP for 2 h pDNA was labeled with YOYO-1, the lysosomes were stained with LysoTracker Red, while the nuclei were stained with Hoechst 33342. (D) Cell viability of 4T1 cells after 24 h incubation with nanocarriers of different concentrations. Data were presented as mean ± SD (n = 3). (E) Time-dependent gene expression of mCherry after different irradiation time. Cells were incubated with pGCherry@PVHRs NP for 6 h in dark, fresh medium was replaced and cells were cultured under blue light (2 W/m²) for 4, 6 or 8 h. (F) Mean fluorescence intensity of mCherry was quantitatively analyzed by ImageJ. Data were presented as mean ± SD (n = 3).